content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2012, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
   * Other names may be trademarks of their respective owners.]
   *
   * --------------------
   * HexNumberFormat.java
   * --------------------
   * (C) Copyright 2007, 2008, by Richard West and Contributors.
   *
   * Original Author:  Richard West, Advanced Micro Devices, Inc.;
   * Contributor(s):   David Gilbert (for Object Refinery Limited);
   *
   * Changes:
   * --------
   * 14-Jun-2007 : Version 1 (RW);
   *
   */
  
  package org.jfree.chart.util;
  
  import java.text.FieldPosition;
  import java.text.NumberFormat;
  import java.text.ParsePosition;
  
  /**
   * A custom number formatter that formats numbers as hexadecimal strings.
   * There are some limitations, so be careful using this class.
   *
   * @since 1.0.6
   */
  public class HexNumberFormat extends NumberFormat {
  
      /** Number of hexadecimal digits for a byte. */
      public static final int BYTE = 2;
  
      /** Number of hexadecimal digits for a word. */
      public static final int WORD = 4;
  
      /** Number of hexadecimal digits for a double word. */
      public static final int DWORD = 8;
  
      /** Number of hexadecimal digits for a quad word. */
      public static final int QWORD = 16;
  
      /** The number of digits (shorter strings will be left padded). */
      private int m_numDigits = DWORD;
  
      /**
       * Creates a new instance with 8 digits.
       */
      public HexNumberFormat() {
          this(DWORD);
      }
  
      /**
       * Creates a new instance with the specified number of digits.
  
       * @param digits  the digits.
       */
      public HexNumberFormat(int digits) {
          super();
          this.m_numDigits = digits;
      }
  
      /**
       * Returns the number of digits.
       *
       * @return The number of digits.
       */
      public final int getNumberOfDigits() {
          return this.m_numDigits;
      }
  
      /**
       * Sets the number of digits.
       *
       * @param digits  the number of digits.
       */
      public void setNumberOfDigits(int digits) {
          this.m_numDigits = digits;
      }
  
      /**
       * Formats the specified number as a hexadecimal string.  The decimal
       * fraction is ignored.
       *
       * @param number  the number to format.
       * @param toAppendTo  the buffer to append to (ignored here).
       * @param pos  the field position (ignored here).
       *
       * @return The string buffer.
       */
      @Override
      public StringBuffer format(double number, StringBuffer toAppendTo,
              FieldPosition pos) {
          return format((long) number, toAppendTo, pos);
      }
  
      /**
       * Formats the specified number as a hexadecimal string.  The decimal
       * fraction is ignored.
       *
       * @param number  the number to format.
       * @param toAppendTo  the buffer to append to (ignored here).
       * @param pos  the field position (ignored here).
       *
       * @return The string buffer.
       */
      @Override
      public StringBuffer format(long number, StringBuffer toAppendTo,
              FieldPosition pos) {
          String l_hex = Long.toHexString(number).toUpperCase();
  
          int l_pad = this.m_numDigits - l_hex.length();
          l_pad = (0 < l_pad) ? l_pad : 0;
  
          StringBuffer l_extended = new StringBuffer("0x");
          for (int i = 0; i < l_pad; i++) {
              l_extended.append(0);
          }
          l_extended.append(l_hex);
  
          return l_extended;
      }
  
      /**
       * Parsing is not implemented, so this method always returns
       * <code>null</code>.
       *
       * @param source  ignored.
       * @param parsePosition  ignored.
       *
       * @return Always <code>null</code>.
       */
      @Override
      public Number parse (String source, ParsePosition parsePosition) {
          return null; // don't bother with parsing
      }
  
  }
  